1. Field of the Invention
The present invention relates to a thermistor fixing structure, a thermistor removing method, and an air-conditioning apparatus, and more particularly, to a thermistor fixing structure having a thermistor fixed to a temperature sensitive cylinder thereof, a thermistor removing method for removing the thermistor fixed to the thermistor fixing structure from the temperature sensitive cylinder, and an air-conditioning apparatus including the thermistor fixing structure.
2. Description of the Related Art
Hitherto, as a thermistor fixing structure, for example, the following invention is disclosed (see, Patent Literature 1). In this invention, a temperature sensitive cylinder is brazed to a temperature detection portion of a refrigerant pipe of a refrigeration cycle apparatus, which is a part to be subjected to temperature detection, and a columnar thermistor is inserted into the temperature sensitive cylinder and fixed in such a manner that the thermistor is pressed against an inner surface of the temperature sensitive cylinder with a leaf spring.
Patent Literature 1; Japanese Utility Model Application No. Sho 57-168819 (microfilm of Japanese Utility Model Application Laid-open No. Sho 59-72523) (page 1, FIG. 5)
The leaf spring of the invention disclosed in the Patent Literature 1 has two serial circular-arc (substantially w-shape with smooth peaks) curved sections formed on a strip-like plate member. One end portion of the leaf spring is bent into a substantially C-shape to form a locking section, and the other end portion of the leaf spring is bent into a substantially L-shape to form an abutting section.
Thus, when the curved sections of the leaf spring are inserted into the temperature sensitive cylinder, the locking section of the leaf spring is locked onto an outer surface of the temperature sensitive cylinder from one end surface side thereof, and the abutting section of the leaf spring is brought into abutment against the other end surface of the temperature sensitive cylinder, the leaf spring does not easily drop off the temperature sensitive cylinder. In this state, when the thermistor is inserted into the temperature sensitive cylinder, the thermistor is pressed against the inner surface of the temperature sensitive cylinder with a spring force of the leaf spring (corresponding to an elastic restoration force of each curved section).
In the invention disclosed in the Patent Literature 1, however, the peaks of the two curved sections formed on the leaf spring are configured to be brought into contact with the thermistor, and each of the peaks is formed into a shape of a circular arc having a relatively large curvature radius. Therefore, the thermistor is easily insertable into the temperature sensitive cylinder while overcoming the spring force of the leaf spring (to be accurate, a frictional force caused by the spring force), but at the same time, the thermistor is easily removable from the temperature sensitive cylinder to the outside.
In this case, there is a problem in that, for example, when a lead wire connected to the thermistor is unintentionally pulled at the time of assembling, or when the lead wire is caught on any portion, the thermistor is easily detached from the temperature sensitive cylinder.
When the spring force is increased so as to prevent the thermistor from being easily detached from the temperature sensitive cylinder, on the other hand, a greater force is required to insert the thermistor into the temperature sensitive cylinder, thereby leading to a problem in that the workability is degraded.